In the second film, linking The Hobbit and The Lord of the Rings, I wonder if there would be a decent way to fit 'The Scouring of the Shire' in somewhere, without confusion to those who haven't read the books. Those who have read the books, however, will be very happy to see that chapter added, I'm sure. It was an important detail in The Return of the King that would have made the film too long for most people to sit through, I suppose. So it might make since to add it to The Hobbit's sequel.

Have good fortune on the journey ahead. Namarie! I would have gone with you to the end, into the very fires of Mordor.